Fire-resistant polymers

Phosphorus-Based Polymers From Synthesis to Applieations 

The chapter will conclude with some observations about the challenges to be met before this and any other pioneering polymer system can find its way into the commercial sector. 

A number of routes have been developed for the synthesis of poly(organophos-phazenes). The main methods are deseribed in Seetions 7.2.1-7.2.4. 

Cyclic Chlorophosphazene such as (NPCya, followed by Replacement of the Chlorine Atoms in the Resultant Chlorophosphazene High Polymer by Organic Groups 

One of the advantages of the macromolecular substitution route is the ease of introduction of two or more different substituents. In a sense this is a 

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To conclude this synthetic section, it appears very clear that the experimental approaches for preparation of POPs are very numerous and give accessibility to phosphazene polymers and copolymers with different structures and properties. Moreover, it has been recently estimated [10,383] that the total number of polyphosphazenes reported up to now in the literature is about 700, and that these materials can find potential practical application as flame- and fire-resistant polymers [44,283, 384-388] and additives [389, 390] thermally stable macromolecules [391] chemically inert compounds [392] low temper-... 

The grade. An inherently flammable polymer can be VO classified for a special fire-retardant grade or, vice versa, an inherently fire-resistant polymer can be HB classified for a special grade containing too high a level of flammable plasticizer. 

The U.S. Federal Aviation Administration (FAA) developed the Microflow Combustion Calorimeter to assist with the development of fire-resistant polymers for use in commercial passenger aircraft. A schematic of this microscale calorimeter is shown in Figure 14.10. The apparatus is described in ASTM D 7309. 

Fire resistant polymers were obtained from brominated epoxynovolak resin, BPA/DC prepolymer, BMI, Zn acetate and benzoyl peroxide [103] or from an oligo-aspartimide (BMI-diamine reaction product), BPA/DC, 2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane (i.e. Tetrabromo-Bisphenol A) and 2-ethyl-4-methylimi-dazole [104]. A mixture of BPA/DC, BMI and epoxide resin with brominated polycarbonate, copoly[oxy-2,6-dimethylphenylene)-(oxy-2,3,6-trimethylphenylene)] and a catalyst was also suggested [105],... 

Rusanov, A.L. Korshak, V.V. Heat- and fire-resistant polymers based on chloral and its derivatives. Uspekhi Khimii 1989, 58, 1006-1031. 

Lyon, R. Fire resistant polymers based on bisphe-nol-C. International Aircraft Fire and Cabin Safety Research. Atlantic City, NJ, 2001. 

In this chapter, attention is focused on a number of polymers that are either themselves characterized by special properties or are modified for special uses. These include high-temperature and fire-resistant polymers, electroactive polymers, polymer electrolytes, liquid crystal polymers (LCPs), polymers in photoresist applications, ionic polymers, and polymers as reagent carriers and catalyst supports. 

As mentioned above, the thermal stability of polymers is closely tied to the manifestation of fire-protection properties. Many factors causing the stability of the materials to the exposure of high temperatures are characteristic for the fire-resistant polymers too. 

Very intensive research into thermal and fire resistant polymers continues. An interesting target of these investigations is the cyclophosphazene polymers. The studies aim not only at the development of new more heat-resistant and less combustible resins but also at improving the processability of the current grades. These efforts have lead to the commercialization of a large number of thermally stable resin grades, as listed in Table 5.17. 

Give two methods for making thin films of the following inorganic polymers (a) MEEP (b) Dexil (c) a fire-resistant polymer (d) an anion-conducting polymer membrane. 

Chapter 7 by Allcock and Pugh describes the family of polyphosphazene polymers that have a structure based on a backbone of alternating phosphorus and nitrogen atoms, and with two organic side groups attached to each phosphorus. The authors of this chapter show that polyphosphazenes are mostly synthesized by a macromolecular substitution method in which a reactive intermediate, polydichlorophosphazene, is used as a substrate for the replacement of the chlorine atoms by organic nucleophiles. The potential uses for these polymers are in the field of aerospace, fire resistant polymers, fuel cells, and also for biomedical applications. 

The LOI is greater than 22.5 for what are called fire-resisting polymers and greater than 27 for the self-extinguishing types (see Table 24-1). In general, the LOI increases by about one-seventh its value on doubling the mass/surface area ratio of the test material ( material weight ). This increase in the LOI can be attributed to hindered diffusion. 

Major Applications Inks,4 fire-resistant polymers, permanent hair straightener ... 

Flame-retardant films These are based on fire-resistant polymers that contain halogenous or phosphorous flame retardants which act in the gas phase. 

There is currently a tendency to partially substitute antimony trioxide by metaborates or borates of zinc, barium and oxides of other metals in the development of new, fire resistant polymer materials [110-112]. Intensification of the action of the mixture of Sb203 with Fe203 and CuO and also with 2ZnO.3B2O3.5H2O is related to its reduction of the activation energy of SbOCl decomposition [113]. 

Fire resistant polymers. 2. Nanocomposites (Materials) I. Mittal, Vikas. II. Title. TH1074.5.T535 2011 677. 689-dc22 2010048227... 

Polyimides (Pis) were the first so-called high-heat-resistant plastics. They in fact retain a significant portion of their room-temperature mechanical properties from - 240 to 315°C (-400 to +600°F) in air. Pis, which are available in both TPs and TSs, are a family of some of the most heat- and fire-resistant polymers known. As discussed in connection with some of the other polymers, there are others that have heat resistance in the 260°C (500°F) range. 

Fire resistant polymers. 2. Nanostructured materials. 3. Polymeric composites. I. WiUde C. A. (Charles A.) II. Title. 

This polymer was of interest to the Materials Laboratory and they had it developed by the Celanese Company to give probably the best heat resistant and fire resistant polymer that has been made. Its expense has prevented it from ever becoming very widely used. But it is oxidatively stable to about 300 C and it will not support combustion although it will burn slowly with direct flaming. It has a tensile strength comparable to a good nylon and it makes a comfortable fabric to wear because it transports moisture. 

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